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                                                                   EXHIBIT 10.13

                              CALL OPTION AGREEMENT

                                     Between

              BEIJING QIAN CHENG SI JIN ADVERTISING COMPANY LIMITED

                                       and

                                 51NET.COM INC.

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                              Call Option Agreement

This Call Option Agreement (the "AGREEMENT") is made and entered into as of
August 1, 2002 by and between:

(1)   BEIJING QIAN CHENG SI JIN ADVERTISING COMPANY LIMITED, a limited liability
      company organized and existing under the PRC Law, with its registered
      office at the premises of the Government of Yujiawu Hui Nationality
      Township, Tongzhou District, Beijing, PRC (the "PARTY A"); and

(2)   51NET.COM INC., a company organized and existing under the laws of the
      British Virgin Islands, with its registered office at c/o Offshore
      Incorporation Centre, P.O. Box 957, Road Town, Tortola, British Virgin
      Islands (the "PARTY B").

WHEREAS:

(1)   Qianjin Network Information Technology (Shanghai) Company Limited ("TECH
      JV"), a Chinese-Foreign joint venture company organized and existing under
      the PRC Law, and its business scope is to design and develop software,
      multi-media and network system, related applications and relevant
      information services, design and produce Internet advertisements, launch
      Internet advertisements through www.51job.com, and provide career services
      and human resources (HR) services (operated with licenses, if required);

(2)   Shanghai Qianjin Culture Communication Company Limited ("ADCO"), a limited
      liability company organized and existing under the PRC Law, and its
      business scope is to design and produce all kinds of advertisements, and
      represent as agency for domestic advertisement (operated with licenses);

(3)   Party A owns 1% of the total issued and outstanding shares of Tech JV, and
      20% of the total issued and outstanding shares of AdCo; and

(4)   Party A desires to sell to Party B and/or a company or person designated
      by Party B and Party B and/or a company or person designated by Party B
      desires to purchase from Party A 1% of the total issued and outstanding
      shares of Tech JV and 20% of the total issued and outstanding shares of
      AdCo subject to the PRC laws.

NOW THERFORE, upon friendly consultations and based on a principle of equality
and mutual benefits, Party A and Party B hereof agree as follows:

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                              ARTICLE I DEFINITIONS

1.1   Unless otherwise defined hereof, the following terms shall have the
      following meanings:

"APPROVAL"        any approval, consent, license, permit obtained from and/or
                  issued by any PRC administrative authority in accordance with
                  the PRC Law, including without limitations the approval of
                  government authority of foreign trade and economy regarding
                  the establishment of foreign investment enterprises ("FIE")
                  and any change accordingly;


"OPTION"          the right of Party B and/or the company or person designated
                  by Party B to acquire from Party A 1% of the total issued and
                  outstanding shares of Tech JV and 20% of the total issued and
                  outstanding shares of AdCo in accordance with the terms and
                  conditions of this Agreement;

"PRC"             the Peoples' Republic of China, for purposes of this
                  Agreement, excluding Hong Kong, Macao and Taiwan;

"PRC LAW"         all the laws, regulations and decisions made and promulgated
                  by any PRC legislature, and all the administrative
                  regulations, rules and measures and other official documents
                  legally binding (on the parties hereto);

"REGISTRATION"    any legal registration with relevant PRC authorities upon the
                  application in accordance with the PRC Law, including without
                  limitations the registration with relevant administration for
                  industry and commerce for the establishment and change of the
                  FIEs;

"SHARES"          the equity interests which investor holds by contributing to
                  the registered capital of the company or purchasing or
                  otherwise lawfully acquiring the capital contribution from the
                  original investor of the company. The percentage of the equity
                  shares held by a shareholder in the company shall be equal to
                  his or her proportionate contribution to the registered
                  capital of the company.

                                ARTICLE II OPTION

2.1   Party A hereby irrevocably grants Party B the Option, after which Party B
      shall have the right to purchase from Party A 1% of the total issued and
      outstanding shares of Tech JV and 20% of the total issued and outstanding
      shares of AdCo held by Party A.

2.2   Subject to the PRC Law, Party B and/or a company or person designated by

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      Party B shall have the right to exercise the Option under the terms and
      conditions of this Agreement at any time during the term of this Agreement
      to acquire from Party A 1% of the total issued and outstanding shares of
      Tech JV and 20% of the total issued and outstanding shares of AdCo.

2.3   Upon the request of Party B and/or a company or person designated by Party
      B to exercise the Option, Party A is obligated to transfer the Shares to
      Party B and/or the company or person designated by Party B.

                                ARTICLE III PRICE

3.1   Party A and Party B hereof agree that, for the Option granted by Party A
      and for the 1% of the total issued and outstanding shares of Tech JV and
      20% of the total issued and outstanding shares of AdCo acquired from Party
      A, Party B will pay Party A in the total amount of RMB1.2 Million as a
      consideration.

3.2   Party B and/or the company or person designated by Party B exercise all
      the Option, and acquire 1% of the total issued and outstanding shares of
      Tech JV and 20% of the total issued and outstanding shares of AdCo from
      Party A. Regarding the foresaid share transfer, Tech JV and AdCo shall
      have gone through the formalities of approval and registration. Within
      five (5) days following the issuance of a new Approval Certificate and a
      Business License for Enterprise Legal Person from the approval and
      registration authorities (or the issuance of relevant approval and
      registration certificates by the authority in charge of the exercise of
      the Option), Party B shall deliver the full payment as stipulated in
      Article 3.1 hereof in a lump sum.

                          ARTICLE IV EXERCISE OF OPTION

4.1   Party A and Party B hereof agree that no entity or person other than Party
      B and/or the company or person designated by Party B shall have the right
      to exercise the Option.

4.2   Party B and/or the company or person designated by Party B shall have the
      right to exercise the Option by the means as permitted by law at any time
      after this Agreement becomes effective.

4.3   Subject to the PRC Law, Party B and/or the company or person designated by
      Party B shall be entitled to exercise the Option in whole or in part, and
      on one or more occasions pursuant to this Agreement.

4.4   When Party B and/or the company or person designated by Party B decides to

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      exercise the Option, it shall issue to Party A an OPTION NOTICE (which
      form is attached as Appendix 2). Once the Option Notice is issued, Party A
      shall transfer to Party B and/or the company or person designated by Party
      B the Shares as stipulated on the Option Notice pursuant to this Agreement
      and the Option Notice.

4.5   Party A shall, within 60 days following the issuance of the Option Notice,
      assist Party B and/or the company or person designated by Party B to
      assist Party B and/or the company or person designated by Party B in
      completing all the Approval and the Registration procedures necessary for
      the transfer of the Shares from Party A to Party B and/or the company or
      person designated by Party B.

                    ARTICLE V REPRESENTATIONS AND WARRANTIES

5.1   Party A hereof represents and warrants to Party B and/or the company or
      person designated by Party B that as at the date of this Agreement and at
      the time when Party B and/or the company or person designated by Party B
      exercises the Option in accordance with this Agreement:

      5.1.1 Party A is a limited liability company organized and existing under
            the PRC Law;

      5.1.2 Party A has gone through all necessary corporate procedures and has
            obtained all necessary authorizations and consents for the execution
            and performance of this Agreement;

      5.1.3 Party A has paid up all its proportionate capital contribution in
            Tech JV and AdCo and Party A owns 1% of the total issued and
            outstanding equity interest in Tech JV and 20% of the total issued
            and outstanding equity interest in AdCo, and Party B has no
            obligation to contribute any contributions to Tech JV or AdCo after
            Party B acquires the Shares;

      5.1.4 Party A represents and warrants that, the Shares it owns in Tech JV
            and AdCo are free from any option, pledge, or any other security
            interests or encumbrance with the same legal effect, or any
            undertakings or obligations of the foresaid encumbrance, and no
            option, pledge, or any other security interests or encumbrance with
            the same legal effect, or any undertakings or obligations of the
            foresaid encumbrance may be set on such Shares Party B's written
            consent; and without Party B's written consent, Party A shall not
            transfer any of the Shares it owns in Tech JV or AdCo to any third
            party;

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      51.5  the execution and performance of this Agreement will not cause Party
            A to violate any of its obligations in any legal binding documents
            that Party A is a party, or constitutes a violation of the PRC Law
            and/or any injunction or order or decree of any court, arbitration
            tribunal or administrative agency; and

      5.1.6 no litigation, arbitration, governmental investigation, penalty or
            other similar material events is pending upon or is threatened to be
            initiated against Party A, which has or would have an adverse effect
            upon the matters stipulated hereof.

5.2   Party B hereof represents and warrants to Party A that as at the date of
      this Agreement:

      5.2.1 Party B is a limited liability company organized and existing under
            the laws of the British Virgin Islands; and

      5.2.2 the execution and performance of this Agreement will not cause Party
            B to violate any of its obligations in any legal binding documents
            that Party B is a party, or constitutes a violation of any
            injunction or order or decree of any court, arbitration tribunal or
            administrative agency.

                              ARTICLE VI INDEMNITY

6.1   If Party B hereto discovers, after the Shares have been transferred to
      Party B and/or the company or person designated by Party B in accordance
      with this Agreement, that any of the representations and warranties made
      by Party A under this Agreement is false or inaccurate, then Party B has
      the right to request Party A to correct or cure the false or inaccurate
      circumstance so that the non-conforming circumstance is consistent with
      the applicable representations and warranties hereof. In the event that
      Party A is unable to correct or cure such non-conforming circumstance by
      then, Party B shall have the right to cure the foresaid situation and any
      costs and expenses incurred shall be borne by Party A, and Party A shall
      also be liable for any and all losses and costs that Party B and/or the
      company or person designated by Party B has suffered in connection with or
      arising from the aforementioned false or inaccurate representation and/or
      warranties made by Party A.

6.2   If any party hereto defaults or violates any of its obligations hereof,
      the defaulting party shall compensate the non-defaulting party for any
      loss incurred or suffered by the non-defaulting party in connection with
      or arising from the aforementioned defaults or violations.

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                           ARTICLE VII CONFIDENTIALITY

7.1   Unless otherwise stipulated hereof, Party A and Party B shall use their
      best endeavors to keep the following information in confidential, (1) any
      business information in connection with the other party which was obtained
      from the execution and performance of this Agreement, (2) any contents
      hereof and (3) matters in connection with any potential cooperation the
      parties may have. Any Party hereof shall limit its employees, agents and
      others to obtain the foresaid information only when it is necessary to
      perform the responsibilities and obligations of this Agreement.

7.2   Parties hereof shall cause its directors, officers and other employees and
      the directors, officers and other employees of any of its affiliates to
      abide by this clause.

                        ARTICLE VIII FORCE MAJEURE EVENT

8.1   Force Majeure Event shall refer to any uncontrollable, unforeseeable or
      unpreventable event of either party or both parties hereof, occurred after
      the date of this Agreement, which caused any party hereof unable to
      perform all or part of this Agreement, including without limitation
      explosion, fire, flood, earthquake, or other God act, and war, riots, or
      government act.

8.2   In the event of occurrence of Force Majeure Event, the party affected by
      the event shall promptly notify the other party without any delay and
      shall, within fifteen (15) days of the occurrence of the Force Majeure
      Event, provide a detailed report evidencing the same. The party affected
      by the Force Majeure Event shall take all appropriate means to eliminate
      the effect of the Force Majeure Event or minimize the loss to the other
      party. Both parties shall decide to postpone or terminate the performance
      of the Agreement, or waive part or all obligations and responsibilities of
      the affected party based on the effect of the Force Mejeure Event.

                            ARTICLE IX GOVERNING LAW

9.1   The execution, effectiveness, interpretation and performance of this
      Agreement and the disputes resolution in connection with this Agreement
      shall be governed by the PRC Law.

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                          ARTICLE X DISPUTES RESOLUTION

10.1  All disputes arising from or in connection with this Agreement shall be
      resolved through friendly consultation between both parties hereof. If
      such dispute has not been settled within thirty (30) days after the
      consultation, either party may submit the dispute to China International
      Economic and Trade Arbitration Commission ("CIETAC") in Beijing for
      arbitration in accordance with then effective arbitration rules of CIETAC.
      The arbitration award shall be final and binding upon both parties hereto.

10.2  CIETAC as stipulated in Article 10.1 shall decide on which party bears the
      arbitration costs.

10.3  During the disputes, both parties hereto shall continue to perform the
      duties and obligations under this Agreement not the subject of the
      disputes.

                            ARTICLE XI EFFECTIVENESS

11.1  This Agreement shall become effective upon the date when the respective
      authorized representative of Party A and Party B executes and signs on
      this Agreement. The term of this Agreement is ten (10) years. Upon a
      written agreement between both parties, this term may be extended
      afterwards.

                               ARTICLE XII NOTICE

12.1  Any notice made under this Agreement shall be delivered to the other party
      by hand, facsimile or registered airmail. Seven (7) days of the postmark
      shall be deemed to be the date of the receipt if delivered by airmail, and
      the date of the delivery of a notice if delivered by hand. In the event
      that the notice is sent by facsimile, after the notice is sent by
      facsimile, the original copy shall be delivered to the other party by
      registered airmail or by hand.

              ARTICLE XIII LANGUAGE, COUNTERPARTS AND MISCELLANEOUS

13.1  This Agreement may not be changed, modified or amended in any way except
      by a written agreement agreed and signed by both parties.

13.2  In the event that any provision under this Agreement becomes ineffective,
      invalid or otherwise unenforceable, the effectiveness, validity and
      enforceability of other provisions hereunder shall not be affected or
      otherwise damaged, provided that both parties hereto shall immediately
      cease the performance of such ineffective, invalid or unenforceable
      provision, and correct

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      such provision, to the extend that such correction is the most close to
      the original intent of such provision, until such provision becomes
      effective, valid and enforceable.

13.3  This Agreement shall be written in two (2) counterparts in Chinese, one
      (1) for Party A and one (1) for Party B.

13.4  Party A and Party B shall cause their respective authorized representative
      to execute and sign on this Agreement as of the day and year first above
      written.

PARTY A
BEIJING QIAN CHENG SI JIN ADVERTISING COMPANY LIMITED

By:__________________________
Name: Feng Lei

PARTY B
51NET.COM INC.

By:______________________
Name: Rick Yan

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                         APPENDIX I CONFIRMATION LETTER

To: Beijing Qian Cheng Si Jin Advertising Company Limited ("Party A")
    51net.com Inc. ("Party B")

Whereas, Party A and Party B has executed and signed on the Call Option
Agreement, in which Party A grants to Party B and/or the company or person
designated by Party B the option to acquire 20% equity interest in Shanghai
Qianjin Culture Communication Communication Company Limited ("AdCo") owned by
Party A ("Option"), and we, Qianjin Network Information Technology (Shanghai)
Company Limited as a shareholder holding 80% equity interests in AdCo hereof
confirm the following:

      1.    we agree that Party A grants to Party B and/or the company or person
            designated by Party B the option to acquire 20% equity interests in
            AdCo;

      2.    in the event that Party B exercises or designates other company or
            person rather than us to exercise the Option, we hereby waive the
            first right of refusal;

      3.    if, when Party B exercises the Option, the PRC Law requires Party B
            to hold at least 25% equity interests in AdCo, then we hereof agree
            transfer part of the equity interests we owned in AdCo to satisfy
            such requirement;

      4.    we hereof undertakes that, in order to adjust the equity ratio of
            all shareholders in AdCo, we will sign share transfer agreements and
            other documents with Party B and/or other company or person
            designated by Party B who exercise the Option;

      5.    we will use our best efforts to cause AdCo to obtain any approval
            from the relevant PRC authorities regarding the share transfer, and
            complete the registration in change at the administration for
            industry and commerce; and

      6.    after the execution of the Option Agreement, we will not, without
            Party B's written consent, (i) transfer the Shares to any third
            party or impose any pledge on the Shares, or otherwise dispose the
            Shares; (ii) conduct any acts or nonfeasance which may cause any
            loss to the Option and/or any decrease in value of the equity
            interests held by Party A; (iii) establish or otherwise cooperate
            with others as a dormant partner or in a different name to establish
            a company conducting same or similar business with the business of
            AdCo.

Shareholder:
Qianjin Network Information Technology (Shanghai) Company Limited
Date:

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                            APPENDIX II OPTION NOTICE

To:   Beijing Qian Cheng Si Jin Advertising Company Limited

To Whom It May Concern:

In accordance with the Call Option Agreement entered into by and between Beijing
Qian Cheng Si Jin Advertising Company Limited and us, 51net.com Inc., we hereof
inform that we decide to exercise / designate [ ] to exercise [all] or [(__)%
of] the Option.

51net.com Inc.

By: ________________________
Authorized representative:
Title:
Date:

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                       AMENDMENT TO CALL OPTION AGREEMENT

Beijing Qian Cheng Si Jin Advertising Company Limited ("Party A") and 51net.com
Inc. ("Party B") made and entered into the Call Option Agreement ("Option
Agreement") on August 1, 2002 and the Supplement to Call Option Agreement
("Supplemental Agreement") on May 3, 2004. Party A and Party B hereto agree to
enter this agreement as an amendment to the Option Agreement and the
Supplemental Agreement ("Amendment Agreement") as of May 3, 2004, as follows:

1.    Article 3.1 of the Option Agreement provided that "Party A and Party B
      hereof agree that, for the Option granted by Party A and for the 1% of the
      total issued and outstanding shares of Tech JV and 20% of the total issued
      and outstanding shares of AdCo acquired from Party A, Party B will pay
      Party A in the total amount of RMB1.2 Million as consideration"

      The Parties hereby agree that the above provision should be amended as:

      "Party A and Party B hereof agree that, for the Option granted by Party A
      and for the 1% of the total issued and outstanding shares of Tech JV and
      20% of the total issued and outstanding shares of AdCo acquired from Party
      A, Party B will pay Party A an aggregate amount of RMB1.2 Million as
      consideration. If Party B and/or its designated company or individual
      fails to obtain the approval to acquire the foresaid shares at such price
      under the then applicable PRC laws, the Parties agree that Party B and/or
      its designated company or individual will purchase the foresaid shares at
      the lowest price to the extent permitted by the then applicable PRC laws."

2.    Other provisions under the Option Agreement and the Supplemental Agreement
      shall remain effective.

3.    This Amendment Agreement is a part of the Option Agreement and the
      Supplemental Agreement and shall have the same legal effect.

4.    This Amendment Agreement becomes effective upon the day of execution by
      the respective authorized representative of Party A and Party B.

Party A: Beijing Qian Cheng Si Jin Advertising Company Limited

By:   ______________________________

Name:

Title:

Party B: 51net.com Inc.

By:   ______________________________

Name:

Title:

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                       SUPPLEMENT TO CALL OPTION AGREEMENT

Beijing Qian Cheng Si Jin Advertising Company Limited ("Party A") and 51net.com
Inc. ("Party B") made and entered into the Call Option Agreement ("Option
Agreement") on August 1, 2002. Party A and Party B hereto agree to enter this
agreement as a supplement to the Option Agreement ("Supplemental Agreement") as
follows:

1.    Party A agrees to grant Party B and/or the company or individual
      designated by Party B the option to purchase all the equity interest held
      by Party A in the following companies: (i) 30% equity interest in Wuhan
      Mei Hao Qian Cheng Advertising Company Limited, (ii) 10% equity interest
      in each of the following companies: Dalian Mei Hao Qian Cheng Advertising
      Company Limited, Hangzhou Mei Jin Advertising Company Limited, Chongqing
      Qian Cheng Wu You Advertising Company Limited, Kunming Mei Hao Qian Cheng
      Advertising Company Limited, Shanghai Cheng An Human Resources Company
      Limited, Shanghai Wang Cai Trading Company Limited, and Hefei Wu You
      Culture Communication Company Limited, (iii) all equity interest to be
      held by Party A in any entities which Party A may establish in the future.

2.    Party A and Party B hereto agree that the price to be paid by Party B
      and/or the company or individual designated by Party B in consideration of
      the equity interest set forth in clause 1 above shall be the lowest price
      permitted under the laws.

3.    All the provisions under the Option Agreement shall apply to all matters
      hereunder, unless otherwise provided herein.

4.    Shanghai Qianjin Culture Communication Company Limited, another
      shareholder of the companies listed in (1) and (2) in Clause 1 above, has
      agreed to the grant of option to Party B by Party A in accordance with the
      Option Agreement and this Supplemental Agreement. The confirmation issued
      by Shanghai Qianjin Culture Communication Communication Company Limited is
      attached hereto as Appendix A.

5.    This Supplementary Agreement is a part of the Option Agreement and shall
      have the same legal effect.

6.    This Supplementary Agreement becomes effective upon the day of execution
      by the respective authorized representative of Party A and Party B.

Party A:  Beijing Qian Cheng Si Jin Advertising Company Limited

By:   ______________________________

Name:

Party B:  51net.com Inc.

By:   ______________________________

Name:

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                             APPENDIX A CONFIRMATION

To:   Beijing Qian Cheng Si Jin Advertising Company Limited ("Party A")
      51net.com Inc. ("Party B")

Whereas, Party A and Party B entered into the Call Option Agreement on August 1,
2002, and the Supplemental Agreement on May 3, 2004 (hereinafter referred to
collectively as the "Agreement"), whereby Party A grants Party B and/or the
company or individual designated by Party B the option to purchase all the
equity interest held by Party A in the following companies: (i) 30% equity
interest in Wuhan Mei Hao Qian Cheng Advertising Company Limited, (ii) 10%
equity interest in each of the following companies: Dalian Mei Hao Qian Cheng
Advertising Company Limited, Hangzhou Mei Jin Advertising Company Limited,
Chongqing Qian Cheng Wu You Advertising Company Limited, Kunming Mei Hao Qian
Cheng Advertising Company Limited, Shanghai Cheng An Recruitment Services
Company Limited, Shanghai Wang Cai Trading Company Limited, and Hefei Wu You
Culture Communication Company Limited, and (iii) all equity interest to be held
by Party A in any entities which Party A may establish in the future.

NOW, THEREFORE, as the shareholder of the foresaid companies ("Subsidiaries")
listed in Items (1) and (2) above, we, Shanghai Qianjin Culture Communication
Company Limited hereof confirm the following:

1.    we agree to the grant of the foresaid option by Party A to Party B and/or
      the company or individual designated by Party B;

2.    in the event that Party B exercises or designates other company or
      individual other than us to exercise the option, we hereby waive the first
      right of refusal to purchase such equity interest;

3.    we hereby undertake that, in order to adjust the equity ratio of the
      shareholders in such Subsidiaries, we will enter into share transfer
      agreements and other documents with Party B and/or other company or
      individual designated by Party B who exercise the option;

4.    we will use our best efforts to cause such Subsidiaries to obtain the
      approval of relevant PRC authorities regarding the share transfer, and
      complete the registration procedures for any change with the
      administration for industry and commerce; and

5.    we will not, without Party B's written consent, (i) transfer the equity
      interest to any third party or create any pledge on the equity interest,
      or otherwise dispose of the equity interest; (ii) conduct any acts or
      omissions which may hamper the option and/or decrease the value of the
      equity interest held by Party A.

Shareholder: Shanghai Qian Jin Culture Communication Company Limited
By:          ______________________________
Date:        May 3, 2004

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